Aspirin and/or Resistant Starch Have No Effect on Colorectal Cancer Incidence Among People with Lynch Syndrome

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Aspirin and/or Resistant Starch Have No Effect on Colorectal Cancer Incidence Among People with Lynch Syndrome

The use of aspirin and/or resistant starch has no effect on the incidence of colon cancer among individuals with Lynch Syndrome, according to the results of a study published in the New England Journal of Medicine.[1]

Lynch Syndrome, also known as hereditary nonpolyposis colorectal cancer (HNPCC), results from inherited mutations in genes involved in DNA mismatch repair. These mutations greatly increase the risk of developing colorectal cancer. In individuals with an HNPCC mutation, the average age at diagnosis of colorectal cancer is 44 years, compared with 64 years in the general population. Overall, roughly 3% to 5% of all colorectal cancers are thought to result from HNPCC mutations. Other cancers that are more common in HNPCC families include cancers of the endometrium (the lining of the uterus), ovary, small intestine, ureter, and renal pelvis.

In previous studies the regular use of aspirin or similar agents has been shown to reduce the risk of colon polyps and colorectal cancer.[2] Resistant starch is starch that travels through the small intestine without being digested. As a result resistant starch is sometimes classified as a type of dietary fiber; researchers have speculated that it may provide similar benefits to fiber. Resistant starch is found in many foods, including seeds, legumes, unprocessed whole grains, unripe fruit, and more. In addition, resistant starch can be manufactured through various chemical processes.

Researchers conducted a randomized, placebo-controlled, multicenter trial to evaluate the effects of aspirin and/or resistant starch on the subsequent development of colorectal cancer among HNPCC carriers. The study involved 746 patients at 43 centers who were randomized to receive one of four regimens: aspirin plus placebo, aspirin plus resistant starch, resistant starch plus placebo, and placebo plus placebo. The resistant starch was given in the form of Novelose at 30g per day, and the aspirin was given at a dose of 600 mg per day.

With up to four years of follow-up, the researchers found no significant effects from either the aspirin or the resistant starch. Over a mean period of 29 months, colon polyps or cancer developed in 141 subjects. Of the 693 participants who were assigned to receive aspirin or placebo, cancerous growth occurred in 66 subjects who received aspirin compared with 65 who received placebo. Similarly, of the 727 subjects who were assigned to receive starch or placebo, cancerous growth developed in 67 subjects receiving starch compared with 68 subjects receiving placebo.

The researchers concluded that “the use of aspirin, resistant starch, or both for up to four years has no effect on the incidence of colorectal adenoma or carcinoma among carriers of the Lynch Syndrome.”